6.1 This guide presents techniques on the use of thermocouples and associated equipment for measuring temperature in creep and stress-rupture testing in air at temperatures up to 1800°F (1000°C). The duration of a creep test ranges from a few hours to several thousand hours or more at elevated temperatures, at least partially unattended by operators. Such tests are normally ended before test specimen failure. Stress-rupture tests may operate at higher stresses, higher temperatures, and for shorter times than creep tests, but they normally continue until the specimen has achieved its required life or has failed.

6.2 Since creep and stress-rupture properties are highly sensitive to temperature, users should make every effort practicable to make accurate temperature measurements and provide stable control of the test temperature. The goal of this guide is to provide users with good pyrometric practice and techniques for precise temperature control for creep and stress-rupture testing.

6.3 Techniques are given in this guide for maintaining a stable temperature throughout the period of test.

6.4 If the techniques of this guide are followed, the difference between indicated temperature and true temperature, as used in E139, E292, and E21 will be reduced to the lowest practical level.

1. Scope

1.1 This guide covers the use of ANSI thermocouple Types K, N, R, and S for creep and stress-rupture testing at temperatures up to 1800°F (1000°C) in air at one atmosphere of pressure. It does not cover the use of sheathed thermocouples.

1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.

1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.